Interlocking mechanism.



H. E. LEPPERT.

INTERLOGKING MEGHANISM.

APPLICATION FILED MAR,14,1911.

' Patented Oct. 8, 1912.

'UNITED STATES PATENT onirica.

HENRY E. LEPIERT, OF. NEW BRITAIN, CONNECTICUT, AssIGNoR To THHART 'MANU- FACTURING COMPANY, or HARTFORD, CONNECTICUT, A CORPORATION 0F NEW JERSEY.

INTERLOCKING MECHANISM.

Specication of Letters Patent.

Patented Oct. 8, 1912.

Application led March 14, 1911. Serial No, 614,320.

To all whom it may concern:

Be it known, that I, HENRY E. LEPPERT, a citizen of the United States, residing at New Britain, Hartford county, State of Connectiout, have invented certain new and useful Improvements in Interlocking Mechanism, of which the following is a full, clear, and exact description. j

My invention relates to interlocking mechanism and has for its object to produce a simple multiple plunger device in which the several plungers shall interlock so that only one can be actuated at a time. It is particularly useful in connection with multiple push button switches. i

The following is a description of a multiple push button switch constituting an embodiment of my invention, reference being had to the accompanying drawings, in whicli- Figure 1 shows a side elevation of a switch embodying my invention. Fig. Q is a transverse section through the same on the line .r Fig. 1. Fig. 3 is a vertical section through the same on the line g/-;1/, Fig. Q, with one plunger in closed position. Fig. 4 shows a section on the line 5 2, Fig. 1. looking toward the left. Fig. 5 is a detail of the central plunger. Fig. 6 shows a section of the plunger on the line ifi- 40, Fig.

Referring more particularly to the drawings, 1 is a base carrying four .supports 2 to which is secured a plate 3 carrying contacts 4 having binding nuts 5, by which circuits can be electrically connected to the contacts 4.

6 are two supplemental supports carried by the base 1 being secured thereto by screws 7, 7 These supplemental supports carry a plate S secured thereto by screws 9, 9. The screw 9 also serves as a binding screw by which a common return conductor. can be connected to the plate 8.

The plate 8 and the base 1 have three perforatioiis through which extend plungers having metal slianks 10 andfinsulating outer ends 11. The metal portions have projections 12. Between these projections and the plate 8 are spiral springs 13. The outer shanks each have a circumferential groove 1.4 and the shank of each of the intermediate plungers, in the present instance one in number, has a similar groove 14" with a supplemental circumferential recess 15 (Fig. 5), in which lies a ring 16 whose outer diameter is substantially equal to the diameter of the corresponding perforation in the base 1, less the depth of the groove 14, and whose inner diameter is slightly larger than the diameter of the. shank at the bottom of the recess 15. The thickness of the ring 16 equals the depth o f the recess 15 sothat when one link of the ring is seated in the recess-15, the opposite link is in line with the edge of the perforation in which its plunger lies. The projections 12 engage the base 1 and limit the outward movement of the plungers. The base 1 has a longitudinal recess 17 in which are balls 18 located between the three plungers and adapted to partially enter the grooves therein, the diameter of said balls being equal to the distance between a perforation in the base 1 and the bottom of the groove in the next plunger.

19 is a perforated face plate secured to they base 1 so as to give the same a proper finish.

The pluiigers are all electrically connected with the binding post 9 by the plate 8 and the springs 13. The notch 20 permits the return conductor to be easily led to the screw 9.

IVhen an intermediate plunger is forced in so as to engage its Contact 4, the balls 1S are forced outward into the grooves 14 of the other adjacent plungers, locking them against movement. W'lien either of the outer plungers is forced into engagement with its Contact 4, the ball 18 adjacent thereto is forced into the groove 14 of the adjacent plunger, locking it against movement, and also forcing the ring 16 to one side. The ring 16, when so moved, pushes the other engaging ball 18 into the recess 14 of the third plunger, thus locking 1t also against movement, so that the three plungers are completel interlocked. Since none of the interlocking devices 18 and 1Q pass through a plunger but all engage circumferential grooves, the three plunge-,rs are always free to turn on their axes, so that there is little danger of their cramping or binding, moreover the recesses can .easily be formed without a separate operation.

What I claim is:

1. In an interlocking device, the coinbination of a base, three openings therein, al series of three plungers in said openings re spectively, each plunger having a circ.iin iferential recess, a detent between each pair of adjacent plungers, and a. ring loosely seated at the bottom of the recess in the intermediate plunger and adapted to be engaged series of three plungers in said openings reby each detent. spectively, each plunger having a circuln- 15 2. In an interlocking device, the combinaferential recess, a detent between each pair tion of a base, three openings therein, a of adjacent plungers, a ring loosely seated 5 series of three plungers in said openings reat the bottom of the recess in the intermedispectively, each plunger having a circumate plunger and adapted to be engaged by erential recess, a ball detent bet-Ween each each detent, and springs normally tending 20 pair of adjacent plungers, and a ring loos/ely to retract said plungers.

seated at the bottom of the recess in the in- ,10 termediate vplunger and adapted to be en- HENRY E' LEPPERT' gaged by each ball detent. Witnesses:

3. ln an interlocking device, the combina- H. A. HART,

tion of a base, three openings therein, a S. MOODY. 

